#include<bits/stdc++.h>
using namespace std;
using LL=long long;
using ULL=unsigned long long;
#define rep(i,n) for(int i=0; i<(n); i++)

const ULL M=1000000007;
ULL C[128]={};
ULL powM2[200001];
ULL powMI2[200001];
ULL ans=0;

string S;
int N;

int main(){
 cin>>S; N=S.size();
 powM2[0]=powMI2[0]=1;
 rep(i,N) powM2[i+1]=powM2[i]*2%M;
 rep(i,N) powMI2[i+1]=powMI2[i]*500000004%M;

 rep(i,N){
  char c=S[i];
  ans = ans*2%M;
  ans = (ans+powM2[i]+M-C[c])%M;

  C[c]=(C[c]+powM2[i])%M;
 }

 cout<<ans<<endl;

 return 0;
}